Strand threading mechanism for ring textile machines

ABSTRACT

In an automatic ring textile machine, e.g., a spinning frame, for processing a strand which is equipped with a traveling tender carriage capable of detecting the existence of an abnormal condition at a station on the machine and servicing the station to restore it to normal operation, of the type shown in U.S. Pat. No. 3,403,866, an improved mechanism for threading the strand in the ring is disclosed.

HJHRMC Morton States Patent Dec. 24, 1974 STRAND THREADING MECHANISM FOR RING TEXTILE MACHINES [75] Inventor: Robert Earl Morton, Warwick, R.1.

[73] Assignee: Leesona Corporation, Warwick, R.l.

[22] Filed: Sept. 19, 1973 [21] Appl. No.: 398,591

[52] U.S. Cl 57/34 R [51] Int. Cl D0lh 15/00 [58] Field of Search 57/34 R, 52, 57, 54

[56] References Cited UNITED STATES PATENTS 3,486,319 12/1969 Lee, Jr. et al. 57/34 R 3,540,200 11/1970 Tsukumo et al. 57/34 R 3,552,110 1/1971 Livingston 57/53 3,591,951 7/1971 Urano et a1. 1. 57/34 R 3,628,320 12/1971 Harmon 57/34 R 3,688,486 9/1972 Bell et al 57/34 R 3,728,852 4/1973 Anderson et a1 57/34 R Primary Examiner-John Petrakes Attorney, Agent, or FirmAlbert P. Davis; Burnett W. Norton [57] ABSTRACT In an automatic ring textile machine, e.g., a spinning frame, for processing a strand which is equipped with a traveling tender carriage capable of detecting the existence of an abnormal condition at a station on the machine and servicing the station to restore it to normal operation, of the type shown in US. Pat. No. 3,403,866, an improved mechanism for threading the strand in the ring is disclosed.

17 Claims, 12 Drawing Figures PMENTEDDEW'QT 3,855,769

sum 1 95 g FIG/f STRAND THREADING MECHANISM FOR RING TEXTILE MACHINES This invention relates to automatic multi-station ring textile machines, i.e., a ring twister or spinning ma chine, equipped with an automatically functioning tending or servicing carriage traveling along the sides of the machine and capable of detecting the existence at a strand processing station along the machine of an abnormal condition requiring servicing and of carrying out the necessary operations, including threading of the ring traveler, to restore that position to normal functioning, and is concerned more particularly with an improved mechanism for accomplishing such traveler threading.

Traditionally, ring spinning machines or frames have been tended by manual labor in which a human operator observes a given number of spinning positions, determines when an abnormal condition occurs at a given position, e.g., when a bobbin has been fully wound or the flow of the yarn interrupted, removes the partially or fully wound bobbin if need be, and reunites a broken yarn or threads up the roving onto a fresh empty bobbin in order to restore that position to normal working operation. Needless to say, the cost of manual labor for this purpose is considerable and in recent times textile equipment manufacturers have concentrated heavily on developing equipment that will perform in essentially an automatic fashion the manipulative operations required for servicing such spinning machines. Examples of patents covering such equipment developed by the assignee of the present application and of interest in relation to the present invention include U.S. Pat. Nos. 3,403,866, 3,688,486, 3,724,192 and 3,735,576. Generally similar equipment developed by other companies are disclosed in U.S. Pat. Nos. 3,486,319, 3,540,200 and 3,740,937.

While the systems disclosed in the above-identified patents vary in the details of their design and operation, they are all similar in basic concept and contemplate the association with the ring textile machine, e. g., a ring spinning frame, of a servicing carriage or tender which patrols back and forth along, or endlessly around, the rows of strand processing, e.g., spinning, stations on the sides of each frame while riding on a track affixed to the machine for this purpose. The servicing carriage is equipped with sensing devices for detecting the occurrence at any processing position of an abnormal condition calling for servicing by the tender. Typically, such abnormal conditions include the completion of a fully wound bobbin or an interruption or rupture in the flow of the yarn to the bobbin at a given spinning station. In the first of these conditions, the tender functions to doff the fully wound bobbin from the spindle at that station, don an empty bobbin on that spindle, and then initiate the winding of the yarn on the newly donned bobbin. In the second case, a trailing end may be unwound from the partially wound bobbin and reunited with the spun yarn or, alternatively, the partially filled bobbin can be doffed, a fresh bobbin donned and winding of the spun yarn initiated on the new bobbin as in the first case. After the servicing function is completed and the tender confirms that the station being serviced is restored to normal functioning condition, the tender returns to its patrolling action along the spindle rows until another station is detected which requires servic- As the aforegoing summary suggests, one critical aspect of successfully servicing a ring textile machine is the threading of the yarn through the traveler that rides circuitously around the ring and guides the yarn to the take-up package during winding. This threading step is particularly delicate because of the necessity for accurate positioning of the yarn arcuately around the exterior periphery of the ring channel so that when the traveler is propelled around the ring, the traveler will move over and around the yarn at a point proximate to the top of the ring so as to hook onto the yarn. After becoming hooked in the eye of the traveler, the yarn must then be displaced from the outside channel of the ring to a position stretching chordally across the ring opening and then severed at a point downstream of the ring so as to produce a free strand end which can then be attracted, as by aspiration, into a yarn-engaging means, in the form, for example, of a suction nozzle, and eventually attached onto a take-up bobbin for winding into a package. In the systems disclosed in the aboveidentified commonly assigned patents, especially U.S. Pat. No. 3,403,866, the positioning of the yarn relative to the exterior of the ring rail was accomplished by one mechanism, including a reciprocating threading fork, while the lifting of the yarn after engagement in the eye of the traveler and the severing of the lifted yarn to produce a free end was accomplished by a different mechanism including a combined lift fork and shear blade, the two mechanisms being entirely separate and distinct from one another and utilizing separate actuating means, e.g., hydraulic cylinders.

The object of the present invention is to provide an improved strand threading mechanism in which each of the several operations of thread positioning, lifting and severing is carried out by means of a single consolidated unit actuated by means of a common drive means. A collateral object of the invention is an improved strand threading mechanism in which several manual operations are carried out in a predetermined mechanical sequence which is inherent in the design of the mechanism itself so that the entire ring threading operation can be initiated and completed by a single control direction rather than by multiple control directions as was required in the former system.

The invention also embodies improvements in the thread positioning fork forming a component of the mechanism whereby that fork is adapted for more reliable and flexible operation and affords a degree of selfalignment with respect to the ring to be threaded.

These and other objects of the invention will become more apparent following a reading of the following detailed description considered with reference to the accompanying drawings in which:

FIG. 1 is a perspective view of the strand threading mechanism of the present invention shown in its inoperative or retracted position relative to the ring and supporting rail of the textile machine, the latter being indicated in phantom to avoid obscuring parts of the invention;

FIG. 2 is a view similar to FIG. 1 with the mechanism of the invention in its fully projected operative position;

FIG. 3 is a top plan view looking down on the mechanism in the retracted position of FIG. 1 with the terminal strand-engaging end of the threaded fork being indicated in dotted lines in two intermediate positions;

FIG. 4 is a top plan view similar to FIG. 3 but with the mechanism in fully projected operative position similar to FIG. 2;

FIGS. 5 and 6 are bottom plan views of the apparatus of FIGS. 1 and 2 showing the fully retracted and projected positions respectively of the yarn shear mechanism;

FIG. 7 is an enlarged detail view of the inward end of the threading fork taken in section substantially along line 7-7 of FIG. 3;

FIG. 8 is a top plan view, with certain parts omitted, taken along line 88 of FIG. 7;

FIG. 9 is a detail view in perspective of the threading fork end;

FIG. 10 is a detail view of the cam plate for controlling the path of the threading fork, shown independently of the remainder of the mechanism;

FIG. 11 is a detail view of the fork slide block, taken in section along line l1l1 of FIG. 3; and

FIG. 12 is a vertical section taken in section substantially along line 1212 of FIG. 4, showing the strand lifter mechanism in operative position.

In the above-identified US. Pat. No. 3,403,866, there is disclosed a complete working system capable of carrying out the various operations described in the preceding introduction, including the mechanical instrumentalities necessary to perfonn the step of threading the ring of the ring textile machine. The present improvements are best understood as constituting an improvement in only that aspect of the overall system of the US. Pat. No. 3,403,866 which is concerned with the threading of the ring of the machine, especially as disclosed in FIGS. 17-23 of that patent. Since the details of the remainder of that system have no particular relationship to the present invention and can in any event be fully discerned from an examination of the US. Pat. No. 3,403,866, the disclosure of which is expressly incorporated by reference herein, this description will not be extended to include such details but will be confined to such fragments of the prior machine which constitute the context for these improvements.

Thus, referring to FIG. 1 of the drawings, the ring threading instrumentalities of this invention are carried on a sub-carriage generally designated C which includes a horizontally disposed working platform 22 and along one side of platform 22 an upstanding end wall 24. Along its forward or inner edge, wall 24 is developed into a vertically extending tubular boss 26 which is shaped for sliding engagement with a guide post P, forming part of the main carriage of the overall servicing system which is adapted to move bodily along the length of the textile machine being serviced, as explained above. Post P is fixed on the main carriage against vertical movement, and hence serves as a supporting and guiding element for the sub-carriage C on which the sub-carriage C can travel vertically as necessary for assuming an appropriate position with respect to the ring rail and associated rings of the machine being serviced. To convey the relationship of the subcarriage to the ring rail, a fragment of the rail is depicted in FIGS. 1 and 2 in phantom with the designation R, together with one of the rings S disposed on the top surface of the rail R and having the traveler T engaged on the top flange thereof for circuitous movement therearound. It will be understood that during operation of the machine, a spindle with a bobbin mounted thereon (not shown) extend upwardly through the interior opening of the ring and rail and strand, i.e., of yarn, is wound on the bobbin to form a package, passing through the circuitously moving traveler which serves to hold the yarn clear of the bobbin periphery and guide the yarn thereto as the ring rail reciprocates vertically through a limited stroke in order to displace the yarn windings along the length of the bobbin to build the desired yarn package.

During such normal operation, the sub-carriage C is maintained in a retracted out of the way position on the main carriage until the main carriage has determined the need for servicing at a given processing position on the machine and has come to rest in proper longitudinal alignment with that particular position. At this point, the sub-carriage is brought into vertical alignment with the ring rail so as to position the instrumentalities carried thereon for threading of the ring. The particulars for accomplishing these functions are all disclosed in the US. Pat. No. 3,403,866 and reference may be had to that disclosure as well as the description contained in a commonly assigned application Ser. No. 398,577 filed Sept. 19, 1973 entitled Ring Rail Tracking Arrangement for Ring Spinning Machines," filed concurrently herewith in the name of Eliyn Lesser.

In accordance with the invention, the threading instrumentalities are driven from a single drive shaft 30 which is mounted for rotation about a vertical axis in spaced apart journals 34,36 projecting from the end wall 24 adjacent its outside edge, i.e., the edge remote from ring rail R. The driving power for shaft 30 is derived from a power cylinder 40, either pneumatic or hydraulic, which is situated on the underneath side of subcarriage C and revealed in entirety in FIGS. 5 and 6 with fragments visible in FIGS. 3 and 4. Drive shaft 30 projects entirely through the platform 22 to receive on its lower end a drive arm 42 rigidly affixed to shaft 30 for bodily movement therewith. Power cylinder 40 includes a piston rod 44 having its free end pivotally connected to the drive arm 42 by means of a pin 46 and a clamping bar 48. The bar 48 is pivoted at one end on pin 46 and is clampingly affixed at a point intermediate its length to the free end of rod 44, thereby permitting the axis of power cylinder 40 to be displaced laterally from the pivot axis on arm 42, as is desirable for the particular spacial arrangement of the illustrative embodiment. Power cylinder 40 itself is pivotally affixed to an extension of platform 22 as at 50.

Referring again to FIGS. 1 and 2, drive shaft 30 carries on the portion thereof between journals 34,36 for bodily movement therewith a power lever 52 terminating at its free end in a downwardly bent extension 54 and connected by means of a coil spring 56 to a follower lever 58 pivoted for free swinging movement on shaft 30. Follower lever 58 includes a shoulder 60 on its forward edge for engagement by the downwardly bent extension 54 on power lever 52 so that the latter cannot swing past the former under the tension force of spring 56. On the other hand, power lever 52 can swing away from follower lever 58 by expansion of spring 56 which then biases follower lever 58 in a following direction, providing what is, in effect, a lost motion connection between the two levers 52, S8. Limits on the extent of arcuate travel of follower lever 58 are imposed by means of horizontally extending bolts 62 threaded into upstanding ribs 64 provided for this purpose on platform 22, the bolts being, of course, adjustable to provide some variation in these limits. Ribs 64 and bolts 62 are arranged well below the planes of travel of levers 52 and 58 and cooperate with a downwardly extending post 66 rigidly affixed to the underside of follower lever 58 for engagement with the bolt heads.

The threading instrumentalities are mounted on subcarriage C for sliding movement inwardly and outwardly with respect to ring rail R and to this end subcarriage C is provided along the side thereof opposite end wall 24 in a location clear of tubular boss 26 with a set of spaced parallel guide rods 70 which are secured at their ends in upstanding brackets 72 situated adjacent the inward and outward margins of sub-carriage C with sufficient distance therebetween to accommodate a sliding movement of significant extent. On the guide rods 70 a slide block 74 is mounted for free sliding movement in the space between end brackets 72. Block 74 is pivotally connected to the free end of follower lever 58 via a short link 76 which serves to adapt the arcuate movement of the end of follower lever 58 to the linear path of travel of block 74.

The end portion of the slide block 74 remote from end wall 24 is relieved on its underside to provide a recess-like space 78 for accommodating the outer end of a threading fork assembly generally designated 80. Assembly 80 includes as its main component an elongated body member 82 which at its outer end away from the ring rail is rigidly affixed to a pivot block 84 arranged within recess 78 and connected to the forward corner of an overhanging portion of slide block 74 by a rigid vertically extending pivot pin 86.

The threading fork assembly during operation must undergo certain lateral movements at its operative inner end as well as a linear reciprocating movement and it is important that these lateral movements follow a carefully predetermined pattern. To this end, a cam plate 88 is disposed on the remote section of platform 22 and in plate 88 is formed a cam track or groove 90 for cooperating engagement with a follower roller 92 projecting downwardly for that purpose from the lower surface of pivot block 84 adjacent its outer end (see FIG. ll). As indicated in the drawings, especially FIGS. 3 and 4, slide block 74 is supported in offset fashion from its axis and, to avoid binding of that block on guide rods 70, it is preferred that pivot block 84 be mounted for direct contact with the upper surface of cam plate 88, relieving any torsional forces that might otherwise be applied to guide rods 70. It is thus advantageous for pivot block 84 to be formed of a low friction material, such as nylon or Teflon synthetic resin, or, alternatively, to attach pads of such resinous material to the underside of the block for sliding contact with the cam plate.

The details of the configuration of cam track 90 are seen more clearly in FIG. wherefrom it appears that the track includes an outer short linear section 94 which receives follower 92 in the rest position of the threading fork assembly. Immediately adjacent rest section 94 is a sharply angled dog leg" 96 deviating at approximately a angle toward the end wall 24 of sub-carriage C. Next is a short linear section 98 which merges into a gradually inclined section 100 angling in the opposite direction from dog leg 96 and joining a nearly linear section 102 which covers almost half of the overall track. Finally, there is a terminal oblique section 104 of moderate angularity towards end wall 24 wherein follower 92 is situated when the fork assembly is in its extreme inward position. The generally circular enlargements at each end of track do not actually constitute part of that track in terms of the movement of follower roller 92 and are present for manufacturing and assembly purposes. Incidentally, the brackets 72, mentioned previously as constituting the guiding support for slide block 74, can be conveniently made as part of cam plate 88 as suggested by the drawings.

One of the features of the present invention is the introduction for the threading engaging components at the inner end of fork body 82 of a certain self-aligning action in both directions of movement and this feature will now be explained with particular reference to FIGS. 7 and 8. Pork body 82 is formed as an elongated rectilinear member of inverted channel configuration when viewed in transverse cross-section. Adjacent its inner end, the channel side walls of body 82 are preferably relieved upwardly as at 106 for clearance reasons and at its tip, body 82 supports the strand-engaging sub-assembly generally designated 110. Sub-assembly 1 10 is attached by means of a flat C-shaped clip 1 12 extending in telescoping relation around the end portion of the channel base wall of body 82, being held there with a socket-headed screw 114. The lower end of clip 1 12 is bent downwardly to form a flange 116 and from the upper side of clip 112, adjacent the inward end thereof, project two spaced apart ears 118 which hold between them a horizontal pivot rod 120 supporting for limited pivotal movement in a vertical direction a pivot bracket designated 122. Bracket 122 is of rather complex configuration and includes a lower generally C- shaped section 124 and two spaced apart lugs 126 fitted at their upper ends to the ends of pivot rod 120. One of the lugs 126 is extended outwardly as at 128 and carries at its outward termination a follower pin 130, the function of which will be explained later. Through the spaced apart legs of lower C-shaped section 124 extends a vertically extending pivot rod 132, the lower end of which pivotally supports a horizontally disposed L-shaped bracket 134. Projecting inwardly from the end of L-shaped bracket 134 is a ring tracking shoe 136 formed with an integral vertical leg 138 to fit behind the leg of bracket 134 and being secured thereto by means of the screw 140.

As best seen in FIGS. 8 and 9, the free portion of tracking shoe 136 viewed in plan has a generally wedge or triangular shape tapering to a rounded pointed end as at 142 with the bottom face thereof also slightly tapered towards point 142. One edge of shoe 136 also defines one side of a thread engaging crotch for the strand Y (included in dotted lines in FIG. 8), the other side of the crotch being constituted by an arcuately curved finger 144 developed as an extension from bracket 134. Preferably, tracking shoe 136 and its leg 138 is formed integrally from a low friction plastic material such as nylon or Teflon. Positional stability for tracking shoe 136 is obtained by stretching a tension spring 145 between the flange 116 on clip 112 and a lip 146 bent upwardly from the outer end of L-shaped bracket 134. In the arrangement as represented in the drawings, with the spring engaged in the corner of lip 146 away from platform end wall 24, spring 145 is effective to bias L- shaped bracket 134 and tracking shoe 136 both downwardly with respect to vertical pivot pin 132. Excessive counterclockwise movement of bracket 134 is prevented by a flange 148 bent downwardly from one side of the lower C-section of pivot bracket 122 to engage a side edge of bracket 134 and limit further movement thereof.

In addition to positioning the strand relative to the ring of the textile machine, the mechanism of the invention must be able to impart to the strand an upward lifting motion in order to displace the strand from arcuate contact with the exterior ring periphery into a position extending generally chordally across the top of the ring. This lifting motion is produced by means of a thread-lifter sub-assembly arranged in piggy-back" fashion on top of the body 82 of threading fork assembly 80 and generally designated 150. The principal member of the sub-assembly 150 is a slide bar 151 shaped as an upwardly opening channel, when viewed in transverse cross-section with its bottom wall slidably resting on the top wall of fork body 82 as depicted in FIGS. 3, 4, and 7. To retain slide bar 151 in that position while permitting limited sliding motion thereof with respect to fork body 82, the top wall of the latter is slotted as at 152 and a retainer block 154 is fitted within the interior of fork body 82 with a key 155 engaged in slot 152 and fastened to slide bar 151 by means of spaced apart screws 156 penetrating slot 152. Slide bar 151 is biased in a direction outwardly from ring rail R by a tension spring 158 stretched between a post 160 depending downwardly from assembly body 82 and the nearer of the screws 156, a passageway 159 (FIG. 7) being hollowed out in retainer block 154 to accommodate the end of the spring.

Approximately midway of the length of slide bar 151, a horizontal pin 162 bridges the upstanding walls thereof to serve as a pivot axis for a bell crank 164. This bell crank includes a downwardly extending toe portion 166 projecting through a slot 168 cut in the lower wall of slide bar 151 for that purpose in the region beneath pin 162. Toe portion 166 thus lies in the path of an adjacent edge 170 of a further slot 171 in fork body 82. Consequently, upon movement of the fork body 82 forwardly relative to the slide bar 151, toe portion 166 engages edge 170 rocking the bell crank 164 upwardly. Bell crank 164 also includes an arm portion 172 terminating along its upper edge in a folded over, and normally horizontally extending, flange 174. The flange 174 acts as a support for a lifter finger 176 extending downwardly to one side of both of the slide bar 151 and fork body 82 and terminating along its lowermost edge in a lifter foot 178 preferably provided with a thread engaging notch along its inner edge as is visible in FIGS. 1 and 8.

Relative movement between fork body 82 and slide bar 151 necessary to ultimately result in upward lifting movement of lifter foot 178 is achieved by restraining slide bar 151 against further forward, i.e., inward, movement at a predetermined point of the inward travel of the threading fork assembly while permitting the fork body 82 to move past that point. Thus, a fixed limit post 182 is arranged at a point slightly outwardly of the thread engaging subassembly 110 (see FIG. 7) extending vertically to a point just clear of the path of the travel of the lower most extremities of fork body 82. For engagement with post 182, retainer block 154, which as previously explained is affixed to slide bar 151 for bodily sliding movement therewith, is developed over a short section of its length with a downwardly extending pad 184 that engages post 182 at a given point in the travel of the fork assembly. Pad 184 serves the further desirable function of sliding on the upper surface of cam plate 88 to stabilize and facilitate the composite reciprocating and swinging motion of the entire fork assembly 80.

It will be recalled from the previous description that one of the lugs 126 which pivot on horizontal pivot rod to allow the thread engaging sub-assembly 110 to swing upwardly includes an outwardly projecting extension 128 carrying at its termination a follower pin 130. The purpose of this follower pin is to produce a lifting action on the thread engaging parts of subassembly 110 in cooperation with cam surfaces formed on an extension 186 projecting inwardly from one side wall of slide bar 151 as can be seen in FIG. 7. These cam surfaces appear on the lower edge of extension 186 and include a horizontal section 188 contacted by the follower pin 130 in the rest or inoperative position of the assembly, a downwardly inclined section 190 and an extreme inward horizontal section 192. It will be appreciated that when fork body 82 advances forwardly while slide bar 151 is restrained against such movement the surfaces 188,190,192 will engage follower pin 130 in turn, causing extension 128 to be pivoted downwardly and producing a corresponding upward displacement on the remainder of the thread engaging sub-assembly 110, especially tracking shoe 136.

The final operation achieved by the present invention is the cutting of the yarn after it has been properly positioned in relation to the ring and traveler of the textile machine and the instrumentalities involved in this operation are disposed on the underside of platform 22 of sub-carriage C and are thus best seen in FIGS. 5 and 6. It will be recalled that power cylinder 40, constituting the source of motive power for the entire arrangement, has its piston rod 44 pivoted onto a drive arm 42. Arm 42 is maintained in slightly spaced relation from the under surface of platform 22 by means of a spacing collar not visible in the drawings so as to provide a clearance space therebetween. Into this space extend two spaced apart positioning rollers 202,204 which are rotatably mounted on corresponding stub shafts 206,208 projecting upwardly from drive lever 42 into the clearance space just mentioned. Rollers 202,204 serve to cooperate with a shear actuating bell crank 210 formed at its outer end (away from the ring rail) with a slight dog leg extension 212. In the inoperative or rest position of bell crank 210, depicted in FIG. 5, the lower edge of dog leg 212 (in the directional sense of FIGS. 5 and 6) has been engaged by roller 202, forcing bell crank 210 in a counterclockwise direction to its rest position. During operation, drive lever 42 pivots in a counterclockwise direction and it will be seen that a considerable interval of arcuate travel of lever 42 occurs before roller 204 makes contact with the inclined upper edge of bell crank 210 just inboard of the dog leg 212, which interval is necessary in order for the threading fork assembly to advance through much of its reciprocal motion before the thread shearing instrumentalities come into play. When roller 204 does engage bell crank 210, further counterclockwise rotation of drive lever 42 produces a corresponding clockwise rotation in the shear bell crank 210 which is pivoted to the underside of platform 22 at 214. Swinging movement of bell crank 210 past its desired limits is prevented by means of two detents 216,218 depending from the underside of platform 22 in a position to engage the opposite sides of bell crank 210, as indicated in FIGS. and 6 respectively.

The inwardly directed free end of bell crank 210 carries a set of yarn shear blades including a stationary blade 220 and a movable blade 222 which is pivoted on the bell crank and includes a generally outwardly directed operating arm 224 terminating in a vertically projecting follower pin 226. The latter cooperates with the edges of a shear cam opening 230 cut adjacent the inward end of a supporting plate 232 projecting inwardly from the adjacent corner of platform 22 and is rigidly attached thereto by screws 233. The cam opening 230 includes an arcuately curved lower portion 234 which, when the shear actuating bell crank 210 is in its inoperative position of FIG. 5, acts on follower pin 226 to pivot movable blade 222 away from stationary blade 220 so that the blades are in an open position to receive the yarn. Adjacent arcuate edge 234 is a straight section 236 which allows the shear blades to move bodily with dog leg 212 while remaining in open position until pin 226 encounters an abutment edge 238 at the other end of straight edge 236. Further clockwise movement of dog leg 212 results in pivotal movement of the movable blade 222 to closed position seen in FIG. 6 severing the yarn that has been engaged therebetween.

It will be evident from the aforegoing description that the threading and shearing instrumentalities of the present improvement move in a predetermined path and, consequently, it becomes important for the position of the strand at the beginning and during the threading operation to be equally predetermined so that the strand can in fact be manipulated in the proper manner by these instrumentalities. This is achieved by providing a thread guide plate 240 generally in the shape of an L (see FIGS. 1-4) and attached along its outermost end to supporting plate 232 outboard of shear cam opening 230 by means of screws 242. From its attachment point, guide plate 240 is bent upwardly to insure clearance from the shear follower pin 226 (as indicated in FIG. 7) to provide a generally flat section 244 lying over shear cam opening 230 which receives the tracking shoe 136 when the threading fork assembly is in its outward inoperative or rest position. A thread engaging leg 246 extends from flat section 244 in a direction away from platform wall 24 and includes a thread engaging notch 248 on its outer side in which the strand is disposed in its threading position to constitute a point of reference about which the manipulative travel of the threading and shearing instrumentalities is adjusted. To permit tracking shoe 136 to project and retract freely over thread engaging leg 246 without interference therefrom, that leg, when viewed in crosssection, is shaped in the manner of an arch (shown in FIG. 7) allowing free travel in both directions of shoe 136.

After the strand has been properly positioned with relation to the ring of the textile machine and a free end generated from the strand by the action of the shear blades 220,222, this free end must be engaged for eventual entrapment on the take-up bobbin to initiate winding thereon. In the original US. Pat. No. 3,403,866 mentioned above, such engagement of the yarn was achieved by means of a suction nozzle mounted as a separate unit on the main carriage of the servicing system and positioned independently of the sub-carriage of that system by means of two pressure cylinders providing vertical and horizontal components of motion,

respectively, for that suction nozzle. In accordance with the invention, a further simplification of the original construction results from the association with the sub-carriage C of a nozzle sub-assembly carrying the general designation 250. This nozzle sub-assembly includes a vortex nozzle body 252 with a suction tube 254 projecting upwardly therefrom. A jet pipe 260 also forms part of the nozzle subassembly 250, which pipe delivers a burst or jet of pressurized air in the direction suggested at 262 in FIG. 4 to impinge upon the traveler T and propel the same around the ring into engagement with the positioned yarn. Nozzle body 252 is of the vortex type described in the US. Pat. No. 3,403,866 and, when supplied with pressurized air, produces a vortical current therein before exhausting through the exhaust outlet 258 (seen in FIG. 6), such vortical flow developing a negative pressure or suction in tube 254 to aspirate the yarn into the inlet opening 256 thereof.

It is necessary for the nozzle sub-assembly 250 to be adapted to move from an extended operative position placing the inlet opening of suction tube 254 as well as the tip of jet pipe 260 with the ring, substantially as seen in FIG. 4, to a retracted out of the way position spaced clear of the ring rail, as suggested in FIG. 1. This movement is made possible by constructing the conduits for supplying the nozzle body 252 and the jet tube 260 with the source of pressurized air out of rigid material and using the same as a supporting arm for the nozzle sub-assembly. These conduits take the form of two closely spaced parallel metal pipes 264 which join at their inner ends with a connector block 266 which is interposed to facilitate lateral displacement of the nozzle sub-assembly from the plane of the rigid pipes 264. At their other, i.e., outer, ends, pipes 264 communicate with the exposed ends of a rotary manifold 270 that is secured in a cylindrical socket 272 preferably cast as an integral part of the platform 22 adjacent the tubular boss 26. A lever arm, not seen in the drawings, extends from the other end of rotary manifold 270 for connection to driving means for the nozzle sub-assembly, such as an additional power cylinder omitted from the drawings. Preferably the rotary manifold 270 is developed with separate passageways for supplying pressurized fluid to the vortex nozzle and jet pipe, respectively, to allow for independent control of the timing and pressures of the air supplied thereto and separate supply inlet ports 274 are shown in the drawing at the top of socket 272.

The operation of the present improvements will now be described, starting with reference to FIGS. 1 and 3. As indicated in dotted lines, the strand Y has been drawn downwardly from the delivery roll (not shown) of the textile machine by instrumentalities only peripherally related to this invention and thus omitted from the drawings, along a generally vertical path which brings it into engagement with the notch 248 and thence downwardly therefrom. To recapitulate, the overall objective of this invention is to displace the strand from this starting position into threaded relation with the traveler T situated on the top flange of the ring S of the ring rail R of the textile machine, sever the strand thus engaged to produce a free end downstream in the strand direction from the point of traveler engagement, and to draw that free end downwardly below the ring rail for further manipulation and attachment onto the take-up bobbin to initiate winding thereon. It is assumed that the sub-carriage C has been properly oriented both in the longitudinal direction parallel to the line of rings carried on the ring rail as well as in the vertical direction in a fashion taught in other disclosures incorporated by reference herein as identified above. Hence, as seen in FIGS. 1 and 3, sub-carriage C is already suitably oriented with respect to the ring rail and is moving along a vertical path of reciprocation in synchronization with the normal reciprocation of the ring rail, although for purposes of this description, such reciprocation is immaterial and can be disregarded. The threading fork assembly 80 is, as shown in FIGS. 1 and 3, in its outwardly retracted inoperative position since power cylinder 40 (see FIG. 5) is in its extended position, holding drive arm 42, drive shaft 30 and power lever 52 in their outermost positions. Slide block 74 is likewise in its outermost position on guide rods 70 and follower roller 92 depending from pivot block 84 moving with slide block 74 is in its starting position (designated A) at the outer end 94 of cam track 90 indicated in dotted lines. Threading fork assembly 80 is in its retracted inoperative position with the tracking shoe 136 (at the innermost tip thereof) resting on the flat section 244 of thread guide plate 240. Fork body 82 extends from its pivot axis on slide block 74 inwardly at a slight angle towards end wall 24 of platform 22. Slide bar 151 of the thread lifter sub-assembly is biased by spring 158 to its full forward position on fork body 82 to the extent permitted by the retainer block 154.

The thread shear components (referring to FIG. 5) are in their retracted position by virtue of the engagement of positioning roller 202 with dog leg 212 of the shear bell crank 210, the shear blades 220,222 being open. The nozzle sub-assembly 250 is in a position swung downwardly and outwardly substantially underneath the inner end of sub-carriage C as suggested in FIG. 1 so as to be withdrawn from any possible conflict with other parts of the machine.

Pressurized fluid is now supplied to power cylinder 40 in accordance with a control signal obtained by means described in the commonly assigned patents identified above and forming no part of the present invention so that the piston rod 44 associated with that cylinder being to withdraw from its extended position in telescoping fashion into the interior of the cylinder. This, of course, produces a corresponding pivotal movement by drive lever 42, rotating drive shaft 30 in a clockwise direction (when viewed in FIGS. 1-4), rocking power lever 52 in that same direction. Since follower lever 58 is connected to power lever 52 by means of the heavy duty tension spring 56, follower lever 58 likewise begins to swing forwardly and slide block 74 begins its reciprocation inwardly (to the left in FIGS. 1-4) on rods 70.

Cam track 90 includes immediately adjacent its rest section 94 the dog leg section 96 which acts upon follower roller 92, displacing the outer end of pivot block 84 sharply in the direction of end wall 24 and produces an ooposite swinging motion on the threading fork assembly 80. This brings the thread-engaging subassembly 1 at the inner tip of the threading fork into essentially transverse alignment with the strand Y engaged in the notch 248 of guide plate 240 (stage B as shown in dotted lines in FIG. 3). The corresponding intermediate position B for the follower roller 92 in cam track 90 is shown in dotted lines in FIG. 9.

Follower lever 58 continues to rock clockwise, advancing slide block 74 on rods to carry follower roller 92 through the sections 98 and 100 of cam track 90. Consequently, the thread engaging sub-assembly 110 is brought into contact with strand Y, receiving the strand in the crotch thereof defined by the mutually adjacent surfaces of tracking shoe 136 and the curved finger 144. By this time, shoe 136 has moved upwardly onto and over the leg 246 of guide plate 240, as permitted by the swivel mount therefor, and the entire fork assembly continues to move first forwardly and then obliquely at a gentle angle toward end wall 24 until tracking shoe 136 comes into engagement with the exterior of the outwardly facing channel of ring S, this composite motion being attributable to the angular relationship of sections 98 and 100 of cam track 90. The resultant intermediate positions of the thread engaging sub-assembly and of the follower pin 92 for this stage are shown in phantom in FIGS. 3 and 9 respectively with the designation C.

Once the toe of tracking shoe 136 is lodged within the channel of the ring S, the tracking shoe is adapted to follow the curvature of that channel by virtue of its universal mounting in conjunction with the counterclockwise bias applied to shoe 136 by spring 145. Thus, as the slide block 74 continues to move forward in a substantially straight transverse direction, shoe 136 tracks along the channel of the ring until the fork assembly nears the inward termination of its travel and follower roller 92 enters the final oblique section 104 of cam track 90. The effect of this terminal cam track section 104 is to gradually pivot the fork assembly 80 away from carriage end wall 24 so as to maintain shoe 136 in contact with the ring channel as the shoe passes the point of true tangency with the ring. This brings the thread-engaging sub-assembly 110 and the body 82 to the solid line position seen in FIG. 4, which stage is designated D with the corresponding position of the follower roller being indicated in phantom in FIG. 10. In this condition, the strand extends from crotch between shoe 136 and finger 144 in the sub-assembly 110 arcuately around an approximately arc of the exterior periphery of ring S and onto its point of engagement in the notch 248 of guide plate 240.

By this time, the nozzle sub-assembly 250 has been swung by the actuating means therefor acting to rotate rotary manifold 270 and the supporting conduits 264 about socket 272, so that the tips of suction tube 254 and jet pipe 260 are disposed within the interior of ring S with their upper ends in proximity to a horizontal plane passing through the top flange of that ring. The jet pipe 260 is now supplied with pressurized air and a jet of air 262 is emitted against the interior face of the ring at an oblique angle thereto and this air jet impinges on the traveler T, causing the same to be propelled around the top flange of ring R and become engaged on the strand at the point where the strand moves out of tangency to the ring periphery.

It is now necessary for the section of the thread which is disposed in arcuate relation to the ring periphery within the outwardly facing ring channel to be displaced upwardly over the top flange of the ring to assume a position extending in chordal relation to the ring between the crotch of the sub-assembly of the threading fork assembly and the notch 248 in the thread guide plate 240. As mentioned during the preceding detailed description, this lifting motion of the wrapped yarn is accomplished as a result of relative motion between the fork body 82 and the slide bar 151 of lifter sub-assembly 150. The throw of the lifter foot 178 is relatively small, say about three-sixteenths inch at its extreme inner tip, and, given the disproportionate relationship of the lengths of the arm portion 72 and the toe portion 166 of bell crank 164 which operates the lifter finger 176, only a very small relative displacement in the order of less than on-fourth inch is required between the slide bar 151 and the fork body 82 for the lifting motion to be fully completed, once toe portion 166 has actually made contact with the edge 170 of slot 171 in fork body 82. The timing of the lifting action is arranged to occur coincidentally with the final thrust of the fork body 82 moving to its terminal position represented at stage D. However, since there is considerable slack in the operative relationship of slide bar 151 and fork body 82, which must be taken up before the bell crank toe 166 is actually brought into operative contact with the slot edge, the position of limit post 182 with respect to pad 184 cooperating therewith should be selected such as to initiate the necessary relative motion at the appropriate point.

As thread lifter sub-assembly 150 is displaced relative to the remainder of fork assembly 80, the cam surfaces 188,190,192 carried on extension 186 of slide bar 151 act on arm 128 via follower pin 130 to swing arm 128 downwardly and rock the thread-engaging subassembly 110 upwardly. Thus the tracking shoe 136 is lifted upwardly as it approaches its final stage D position behind the ring S, which assists in promoting the later upward lifting of the strand by the lifter subassembly as already explained.

The final operation, it will be recalled, is the severance of the strand as achieved by the instrumentalities disposed essentially on the underside of platform 22 seen in FIGS. and 6. All of the while drive shaft is rotating under the impetus of power cylinder in order to produce the results already described, lever 42 is participating in that motion, swinging roller 202 away from the tail portion 212 of bell crank 210 while bringing outer roller 204 toward bell crank 210. However, due to the flat inclination of the legs of bell crank 210, lever 42 is able to pivot a considerable distance before roller 204 actually makes contact with an edge of the bell crank. Indeed, in the arrangement shown, such contact does not occur until follower roller 92 nears the end of the final horizontal stretch 102 of cam track 90 just prior to entry into the terminal oblique portion 104 of that track. With continued rotation of drive lever 42, to complete the forward advance of the fork assembly, roller 204 acts on the edge of crank 210, causing that crank to pivot in a clockwise direction about its pivot axis 214 and, at the time the movement of the fork assembly is finished, crank 210 has moved to a point where its inner leg carrying the shear blades has assumed a position nearly parallel with the edge of the platform 22, as indicated in dotted lines in FIG. 5. With crank 210 in this intermediate position, shear blades 220,222 remain open with the thread extending between their separated edges. Even though the fork assembly is now already in fully operative position, and

remains stationary from this point on, power cylinder 40 has not fully completed its stroke and continues to rotate drive lever 42, which is possible by reason of the lost motion connection furnished by spring 56 between the power lever 52 for the fork assembly and the follower lever 58 which actually is linked to that assembly. This final short are or rotation by lever 42 produces a somewhat exaggerated movement at the free end of crank 210, thrusting the same in a clockwise direction (in the sense of FIGS. 5 and 6) so as to seat the strand firmly in the crotch of the shear blades. Since pin 226 associated with movable shear blade 222 has already been brought into contact with the abutment shoulder 238 on the shear cam opening 230, the movable blade is positively pivoted against the fixed blade so as to close the shear and sever the strand.

Preparatory to the shear action just described, pressurized air is supplied to the vortex nozzle body 252 of nozzle sub-assembly 250 so as to generate a suction in the inlet opening 256 of aspirator tube 254, the nozzle subassembly having remained in its operative position beneath the ring during this time for that reason. The path of the yarn before severance passes very close to the inlet opening 256 and, once the free end is released by the shear cutting action, it is immediately attracted by the suction effect of inlet opening 256 and is aspirated into the tube and eventually brought into engagement with the take-up bobbin so as to become attached to the periphery thereof to initiate winding.

The withdrawal of the sets of instrumentalities described from their operative positions back to their starting inoperative positions takes place in precisely the reverse fashion to the sequence of events just described above, escepting shear blades 220,222, and will be obvious. As regards the shear blades, with reference to FIG. 6, as soon as drive lever 42 beings its clockwise return rotation incidental to the projection of piston rod 44 by power cylinder 40, roller 202 comes almost immediately into contact with the dog leg tail 212 of bell crank 210, pivoting crank 210 quickly out of the extended operative position depicted in FIG. 6. The shear blades, however, remain closed until pin 226 engages the curved edge 234 of cam opening 230 and is forced by that edge to move outwardly, swinging the movable shear blade 222 about its pivot axis to return the shear blades to their starting position shown in FIG. 5.

In order to assist in the aspiration into the nozzle opening 256 of the strand from its chordally extending position just prior to actuatin of the shear blades 220, 222, a downwardly opening hood can be provided as at 300 on the appropriate side of the member 82 of the lifter sub-assembly as visible in FIGS. 1, 2 and 9.

Other modifications and variations than those expressly acknowledged throughout this description are, of course, possible within the spirit of this invention.

What is claimed is:

1. In an automatic multi-station textile strand processing machine of the ring and traveler type equipped with a motor-driven traveling tender carriage capable of detecting the existence of an abnormal condition at a processing station on the machine and servicing the station to restore it to normal operation, including rethreading said strand through the ring and engaged in the traveler, said carriage having a sub-carriage arranged thereon for vertical movement in synchronism with the ring, an improved threading mechanism comprising a threader fork assembly mounted on said subcarriage for generally reciprocating travel from an inoperative position spaced from said ring to an operative position to wrap the thread arcuately around the ring, a thread lifting sub-assembly having forward and rear ends and carried on said fork assembly for relative longitudinal displacement, said thread-lifting sub-assembly including a lifter lever rockably carried on said lifter sub-assembly proximate the forward end thereof and having a thread engaging extension projecting therefrom, means on said fork assembly for rocking said lifter lever upon relative displacement of said lifter subassembly, and stop means fixed on said sub-carriage for engaging said sub-assembly at a point intermediate the ends of travel of said assembly to preclude further motion of the sub-assembly while permitting further travel of said assembly.

2. A textile processing machine as in claim 1 including a set of relatively movable thread shear blades mounted on said sub-carriage for bodily movement from an inoperative position to an intermediate position surrounding said thread, and finally to a shear position, means for moving said blade set in time relation to the reciprocation of said fork assembly whereby said blade set reaches said intermediate position coincidentally as said fork assembly reaches its operative position, and means operative upon further movement of said blade set to produce relative movement thereof to sever said thread after the same is wrapped by said fork assembly around said ring.

3. A textile processing machine as in claim 2 including a common drive for moving said fork assembly and said set of shear blades, respectively, and a lost motion connection between said common drive and said fork assembly to permit further movement of said blades after said assembly has reached its operative position.

4. Apparatus for threading a strand in a traveler movable on a ring comprising, strand engaging means, means mounting said strand engaging means for movement between an inoperative position spaced from said ring and an operative position proximate said ring, said strand engaging means including a tracking surface engageable with said ring and operable to wrap said strand around said ring during movement to said operative position, means for extending said strand in an upwardly inclined path over said ring after wrapping of the strand around the ring, and means for propelling said traveler around said ring to engage said strand.

5. Apparatus as set forth in claim 4 wherein said strand extends from a supply source in a path intersecting the path of movement of said strand engaging means between its operative and inoperative positions and terminates in a free end beyond said path of movement, and including shear means for severing said strand to release said free end after said strand is threaded in said traveler.

6. Apparatus as set forth in claim 5 including means for receiving the strand end extending from said supply source and threaded through said traveler after operation of said severing means.

7. Apparatus as set forth in claim 6 wherein said receiving means includes an aspirator.

8. Apparatus as set forth in claim 7 including hood means cooperable with said aspirator to induce said strand end into said aspirator.

9. Apparatus as set forth in claim 6 including means for moving said receiving means between an active position positioned proximate to said strand and an inoperative position displaced from said strand.

10. Apparatus as set forth in claim 5 including guide means for holding the strand in said path of movement of said strand engaging means.

11. Apparatus as set forth in claim 4 wherein said strand engaging means includes a strand guiding finger, a tracking shoe positioned with said finger to define a notch therebetween, said strand being engageable in said notch, and said tracking surface being defined along an edge of said shoe.

12. Apparatus as set forth in claim 11 including means mounting said shoe and finger for movement in horizontal and vertical planes.

13. Apparatus as set forth in claim 4 wherein said ring includes a cylindrical portion and a flange around the top of said cylindrical portion, said mounting means being operable to guide said strand around said cylindrical portion, and said extending means being operable to position said strand against said flange.

14. Apparatus as set forth in claim 4 wherein said mounting means includes a first assembly movable through a limited path of travel, and a second assembly movable through an extended path of travel beyond said limited path.

15. Apparatus as set forth in claim 14 wherein said second assembly mounts said strand engaging means.

16. Apparatus as set forth in claim 15 wherein said strand engaging means is movable in horizontal and vertical planes, said means for extending said strand including cam means mounted on said first assembly and being operable to rock said strand engaging means horizontally to extend said strand in said upwardly inclined path as said second assembly is moved in said extended path.

17. Apparatus as set forth in claim 4 wherein said mounting means is mounted on a tender movable rela- 

1. In an automatic multi-station textile strand processing machine of the ring and traveler type equipped with a motordriven traveling tender carriage capable of detecting the existence of an abnormal condition at a processing station on the machine and servicing the station to restore it to normal operation, including re-threading said strand through the ring and engaged in the traveler, said carriage having a sub-carriage arranged thereon for vertical movement in synchronism with the ring, an improved threading mechanism comprising a threader fork assembly mounted on said sub-carriage for generally reciprocating travel from an inoperative position spaced from said ring to an operative position to wrap the thread arcuately around the ring, a thread lifting sub-assembly having forward and rear ends and carried on said fork assembly for relative longitudinal displacement, said thread-lifting sub-assembly including a lifter lever rockably carried on said lifter sub-assembly proximate the forward end thereof and having a thread engaging extension projecting therefrom, means on said fork assembly for rocking said lifter lever upon relative displacement of said lifter subassembly, and stop means fixed on said sub-carriage for engaging said sub-assembly at a point intermediate the ends of travel of said assembly to preclude further motion of the sub-assembly while permitting further travel of said assembly.
 2. A textile processing machine as in claim 1 including a set of relatively movable thread shear blades mounted on said sub-carriage for bodily movement from an inoperative position to an intermediate position surrounding said thread, and finally to a shear position, means for moving said blade set in time relation to the reciprocation of said fork assembly whereby said blade set reaches said intermediate position coincidentally as said fork assembly reaches its operative position, and means operative upon further movement of said blade set to produce relative movement thereof to sever said thread after the same is wrapped by said fork assembly around said ring.
 3. A textile processing machine as in claim 2 including a common drive for moving said fork assembly and said set of shear blades, respectively, and a lost motIon connection between said common drive and said fork assembly to permit further movement of said blades after said assembly has reached its operative position.
 4. Apparatus for threading a strand in a traveler movable on a ring comprising, strand engaging means, means mounting said strand engaging means for movement between an inoperative position spaced from said ring and an operative position proximate said ring, said strand engaging means including a tracking surface engageable with said ring and operable to wrap said strand around said ring during movement to said operative position, means for extending said strand in an upwardly inclined path over said ring after wrapping of the strand around the ring, and means for propelling said traveler around said ring to engage said strand.
 5. Apparatus as set forth in claim 4 wherein said strand extends from a supply source in a path intersecting the path of movement of said strand engaging means between its operative and inoperative positions and terminates in a free end beyond said path of movement, and including shear means for severing said strand to release said free end after said strand is threaded in said traveler.
 6. Apparatus as set forth in claim 5 including means for receiving the strand end extending from said supply source and threaded through said traveler after operation of said severing means.
 7. Apparatus as set forth in claim 6 wherein said receiving means includes an aspirator.
 8. Apparatus as set forth in claim 7 including hood means cooperable with said aspirator to induce said strand end into said aspirator.
 9. Apparatus as set forth in claim 6 including means for moving said receiving means between an active position positioned proximate to said strand and an inoperative position displaced from said strand.
 10. Apparatus as set forth in claim 5 including guide means for holding the strand in said path of movement of said strand engaging means.
 11. Apparatus as set forth in claim 4 wherein said strand engaging means includes a strand guiding finger, a tracking shoe positioned with said finger to define a notch therebetween, said strand being engageable in said notch, and said tracking surface being defined along an edge of said shoe.
 12. Apparatus as set forth in claim 11 including means mounting said shoe and finger for movement in horizontal and vertical planes.
 13. Apparatus as set forth in claim 4 wherein said ring includes a cylindrical portion and a flange around the top of said cylindrical portion, said mounting means being operable to guide said strand around said cylindrical portion, and said extending means being operable to position said strand against said flange.
 14. Apparatus as set forth in claim 4 wherein said mounting means includes a first assembly movable through a limited path of travel, and a second assembly movable through an extended path of travel beyond said limited path.
 15. Apparatus as set forth in claim 14 wherein said second assembly mounts said strand engaging means.
 16. Apparatus as set forth in claim 15 wherein said strand engaging means is movable in horizontal and vertical planes, said means for extending said strand including cam means mounted on said first assembly and being operable to rock said strand engaging means horizontally to extend said strand in said upwardly inclined path as said second assembly is moved in said extended path.
 17. Apparatus as set forth in claim 4 wherein said mounting means is mounted on a tender movable relative to said ring and traveler. 